Backspacing telegraph printer mechanism



arch 1, 1949. H. ANGEL 2,462,334

BACK SPACING TELEGRAPH PRINTER MECHANISM 2 Sheets-Sheet 1 Filed Aug. 6, 1946 I use 44 '5 Mw? I///// 38 f [m llllll 2 INVENTOR H. ANGEL. W

ATTORNEY March 1, 1949. H. ANGEL BACK SPACING TELEGRAPH PRINTER MECHANISM 2 Sheets-Sheet 2 Filed Aug. 6, 1946 INVENTOR H. ANGEL W M ATTORNEY Patented Mar. 1, 1949 BACKSPACING TELEGRAPH PRINTER MECHANISM Herbert Angel, Brooklyn, N. Y., assignor to The Western Union Telegraph Company, New York, N. Y., a corporation of New York 1946, Serial No. 688,752

Application August 6,

Claims.

Thi invention relates primarily to printing telegraph mechanisms and apparatus, and more particularly to instrumentalities applicable to printing telegraph machines whereby certain printer functions may be accomplished in re sponse to and under the control of one or more received code groups of signals.

It is an object of the present invention to provide a mechanism and control means therefor whereby either the recording medium or the recording mechanism such a the type bars or the type wheel of a page printer, whichever one is normally movable step-by-step in a letter spacing direction, to effect letter and word spacing, is moved step-by-step in a direction opposite to its normal step-by-step movement. In connection with the above, a more specific object of the invention is to provide mechanism operable in conjunction with a telegraph printer whereby the typing unit or the recording medium may be back-spaced by predetermined increments to any position in its path of travel.

A further object of the invention resides in the provision of mechanism of the above type which is readily applicable to existing printing telegraph machines and which may be applied thereto with a minimum of expense.

A still further object of the invention resides in the provision of mechanism applicable to printing telegraph machines whereby the unit normally movable predetermined increments in a letterspacing direction may be back-spaced multiples of these increments on a cycle of operation of the machine.

In accordance with a modified form of the invention it is an object thereof to provide a mechanism which in response to a conditioning signal conditions the printing mechanism to back-space during following signals, which signals are normally effective to advance the printing mechanism in a letter-spacing direction.

In connection with the above, an object of the invention resides in the provision of mechanism to back-space the printing unit following a conditioning signal until an unconditioning signal is received.

The above and further objects of the invention will be more apparent in the following detailed description of a preferred and one modified embodiment of the invention wherein reference is made to the accompanying drawings.

In the drawings- Fig. 1 i a perspective ments of a page printing view of some of the eletelegraph machine with the elements included in the present invention applied thereto and co-operating therewith;

Figs. 2 and 3 are detailed views of a part of the mechanism of Fig. 1 in normal and operative positions, respectively;

Fig. 4 is a perspective view of a modified form of the invention as it may be applied to a page printer; and

Figs. 5 and 6 are detailed views of part of the mechanism of Fig. 4.

Ihe present invention is shown in the drawings in the manner in which it may be applied to a telegraph printer of the type disclosed in U. S. Patent No. 2,231,215, issued February 11, 1941 to P. A. Noxon, and the said patent is hereby made a part of the present application as if fully included herein. Only so much of the mechanism of the said Noxon patent is shown in the accompanying drawings that it is believed necessary to fully comprehend the principles of the present invention, and while the invention is shown applied to this particular printer it will be obvious that the principles thereof may readily be applied to various other specific types of printers.

Referring to Fig. 1, the carriage indicated generally by reference numeral H is suitably guided for to-and-fro movement relative to the stationary printing mechanism and has a feed rack l2 engaging a pinion l3 on the upper end of a shaft [4. The shaft [4 is normally rotated a predetermined amount in a clockwise direction, as viewed from above, whereby the carriage II is advanced in a letter-spacing direction or to the right as shown in Fig. 1. At the end of a line of print or when it is desired to effect a carriage return function for the beginning of a new line, the rack 12 supported on depending arms, such as It, pivotally carried in the carriage is moved out of engagement with the pinion i3. Thereupon the spring drum I! by means of the flexible band 18 is efiective to return the carriage H to an initial position for the beginning of a new line. concomitantly with the carriage-return function the paper supporting platen I5! is normally rotated to advance the recording medium.

The selecting mechanism of the above-described printer includes a set of permutation bars 2| which are set in various combinations in accordance with received code groups of impulses. Following the permuted setting of these permutation bars 2 I, a group of vdrop-in bars 22, only one of which is shown, is permitted to approach the notched edges of the bars and the one opposite an aligned row of notches pivots to a selected position. The thus selected drop-in bar engages the lower end of an associated hook 23 to pivot the same beneath an operating bail 24. The bail 24, controlled by the operating cam 26, thereupon engages the selectively actuated hook 23 to effect the operation of the operating lever to which the hook is attached.

The printing mechanism includes a plurality of operating levers, such as 21, for effecting the various printer functions and somewhat similar operating levers associated with various type bars are operated to effect recording operations. The operating lever 21 shown in the drawing is pivoted at 28 and in the manner described hereinafter effects back-spacing movement of the carriage I I one character space on each selective operation thereof.

In the mechanism as shown and described in the above-mentioned Noxon patent, the shaft l4 has on the lower end thereof a ratchet wheel which is rotated one tooth in conjunction with each letter or word-spacing operation. This ratchet of the NoXon patent corresponds to the ratchet 29, Figs. 1, 2 and 3, of the present application, but in accordance with the present invention the shaft I 4 is formed in two sections, section I4 and section I411. The upper end of section I4a terminates at the point 3| and is engaged by the lower end of the section I4.

The ratchet 29 in the present application is secured to the shaft I4a for rotation therewith and a collar 32 (also secured to the shaft Ma and rotatable with the ratchet 29) has secured thereto a toothed element 33. Normally the toothed element 33 engages a tooth of another ratchet wheel 34 located thereabove which is secured to a sleeve 36 surrounding the upper end of the shaft Ma and the lower end of the shaft I4. An axial slot 38 in the sleeve 36 engages a pin 31 through the shaft I4 whereby the sleeve rotates with the shaft but is movable along the axis thereof. A spring 39 pressing against the top of the sleeve 36 urges the same in a downward direction.

During the normal letter and word spacing operations of the printing mechanism, rotation of the ratchet wheel 29 effects corresponding rotation of the pinion I3 at the upper end of the shaft I4 through the engagement of the toothed element 33 with a tooth on the ratchet wheel 34.

Some of the function performing levers of the printer, when selected and operated, such as those effecting shift and unshift conditioning of the printer, do not during corresponding cycles of operation effect rotation of the ratchet 29, and the function lever 21, which may be termed the back-spacing function lever, is similar in this re-- spect. Accordingly, when the backspacing function lever 21 is selected and operated, the ratchet wheel 29 will not be rotated to advance the carriage II but through mechanism about to be described eifects back spacing of the carriage.

The right-hand end of the function lever 21 as shown in Fig. 1 engages an arm 4| secured to a rock shaft 42. The latter also has secured thereto a second arm 43 which has pivotally mounted in the outer end thereof a hooked member 44. The selective operation of the operating lever 21 through the described elements effects upward movement of the hooked member 44. A hook 46, as shown in Fig. 2, at the lower end of the member 44 in the normal position thereof is below and in operative relation with a flange 41 of the I sleeve 36. Accordingly, as the hooked member 44 moves in an upward direction the sleeve 36 and ratchet 34 also move upwardly to disengage the ratchet 34 and the toothed element 33. Thereupon the spring drum I1 is effective to move the carriage II in a back-spacing direction and through the rack I2 and pinion I3 rotate the shaft I4 and sleeve 36 in a reverse direction. Should the ratchet 34 be held out of engagement with the toothed element 33 for a suflicient length of time, the carriage II would eifect a complete carriage return function and assume a position for the beginning of a new line. However, the ratchet 34 is only momentarily disengaged from the toothed element 33 or only long enough for the ratchet 34 to escape the toothed element 33 one tooth. The hooked element 44 has thereon a cam surface 45 engageable with a fixed element 48 of the printer and as the hooked member moves in an upward direction, the engagement of the cam surface 45 with the fixed element 48 pivots the member 44 and causes disengagement the hook 46 thereon from the flange 41. This action occurs just as the sleeve is raised sufiiciently for the ratchet 34 to clear the toothed element 33 whereupon the sleeve 36 immediately moves in a downward direction so that the toothed element 33 engages the next tooth of the ratchet 34. Thus the ratchet 34 is permitted to rotate in a reverse direction one tooth at a time and during this movement the carriage is back-spaced a corresponding distance.

By having the same number of teeth on the ratchets 29 and 34, the back-spacing of the carriage II during the operation of the back-spacing operating lever 21 is equal to the distance the carriage is moved in a letter-spacing direction during normal operations. By different arrangements in the number of teeth upon the two ratchets, the amount of back-spacing of the carriage II could be varied. For example, if the ratchet 34 had one-half as many teeth as the ratchet 29, the carriage II would back-space two character spaces at time.

In order to prevent back-spacing of the carriage I I when it is in or very near its initial position for the beginning of a new line of print, the carriage I I carries a member 49 adapted with the carriage in such a position to pivot a lever 5i whereby the lower end thereof engaging the hooked member 44 pivots the same and withdraws the hook 46 from out of operative engagement with the flange 41. Thus, even though the back-spacing operating lever 21 may be operated with the carriage in or near its initial position, the hook 46 cannot engage the collar 41 to lift the sleeve 36. a

In the modified embodiment of the invention as shown in Figs. 4, 5 and 6, the carriage I II supporting the platen H9 is advanced in the same manner and by similar elements as disclosed in the above-mentioned Noxon patent. This advancement of the carriage is effected by rotating the ratchet wheel I29 on the shaft II4 to which is also secured the pinion II 3 engaging the rack II2 carried by arms such as II 6 of the carriage. Rotation of the ratchet wheel I29 effects advancement of the carriage I II in a letter-spacing direction against the action of the spring drum H1 and a carriage return function is effected by moving the rack II 2 out of engagement with the pinion II 3 to permit the spring drum H1 and flexible band II 8 to return the carriage to an initial position for the beginning ofa new line. 7

In accordance with the modified form of the invention, a plate I2I is pivotally mounted adjacent the left-hand end thereof, as best shown in Fig. 6, on the shaft H4 just below the pinion H3. The plate I2I is held in place on the shaft I I4 by a collar I22 and to the right of the pinion I I3 is an idler pinion I23 pivotally mounted on a shoulder screw I20 in the plate I2 I. In the normal position of the plate I2I the teeth of the idler gear I23 do not engage the teeth of the rack I I2 but do engage the teeth of the pinion I I3.

In the modified arrangement, a back-spacing conditioning signal is employed to condition the printer for back-spacing, and following the receipt of such a signal, all other signals which normally are effective on the printer to advance the carriage in a letter spacing direction are effective to back-space the carriage a corresponding distance, and the carriage will continue to be back-spaced by such signals until a restoring signal is received. The back-spacing conditioning operating lever I21 is selected and operated on the receipt of the back-spacing conditioning signal. This lever is selected by pivoting its associated hook I25 beneath the cyclically operating bail I 24. The operating lever I2! is pivoted at I28 and the selective operation thereof through its upwardly extending arm I3I, normally engaging the plate I2I, effects counterclockwise rotation of the plate I2I, as viewed in Fig. 5, against the action of spring I32. This pivoting motion of the plate I2I brings the teeth of the idler pinion I23 into engagement with teeth of the rack H2 and continued movement of the plate I21 causes the rack I I2 to move an amount suificient to withdraw the teeth thereof out of engagement with the teeth of the pinion H3. The amount of movement of the rack H2, however, is not sufiicient to permit the same to be latched in the position to which it is operated in conjunction with the carriage return function.

As the plate I2I is moved into the position shown in full outline in Fig. 5, a latch I33, pivoted at I34 and having an operating spring I36, latches the same in this position. With the rack H2 in engagement with only the idler pinion I23, which rotates in a direction opposite to that of the pinion II3, each following cycle of operation of the printing mechanism wherein the ratchet wheel I29 is advanced will cause the carriage III to back-space a distance equivalent to the distance it normally would be advanced. This backward movement of the carriage while being effected primarily by the spring drum III is governed by the idler pinion I23.

When the carriage H2 is back-spaced the desired amount by the transmission of the necessary number of code groups which normally effect advancement of the carriage, the restoring code group is transmitted to effect operation of the restoring operating lever IZ'Ia. The operation of the restoring lever IZ'Ia by its hook I25 and operating bail I24 causes the same to pivot in a clockwise direction about the pivot bar I31. Such pivoting of the lever I2'Ia causes the end I38 thereof to engage the depending arm of a latch I33 to operate the same and withdraw the hooked arm from out of engagement with the plate I2I. Thereupon the spring I32 is effective to restore the plate to its normal unoperated position and in moving to this position the teeth of the idler gear I23 move out of engagement with the rack I22 and permit the rack to move toward the pinion II3 whereby the teeth thereof reengage those of this pinion. Thus the carriage moving mechanism is restored to its normal position and may be advanced in conjunction with the receipt of the following letter and word spacing signals.

While the invention has been described in but a preferred and one modified embodiment thereof, it will be obvious that various other modifications may be made therein without departing from the spirit or essential attributes thereof, and it is desired therefore that only such limitations be placed thereon as are specifically set forth in the appended claims.

What is claimed is:

1. In a printing telegraph machine, a selector mechanism, a printing unit, a carriage supporting a recording web, movable relative to said printing unit step-by-step in an advancing letter spacing direction and continuously in an opposite and backward direction to effect line-by-line recording on said web, a selectively operable element, means operative by said element to effect backward movement of said carriage relative to said recording unit a predetermined distance on each operation thereof, and means operative by said carriage during a predetermined part of its travel with respect to said printing unit to disable said element to cause backward movement of said carriage.

2. In a telegraph recorder, a carriage normally movable step-by-step in an advancing letter spacing direction in conjunction with printing operations and continuously in a reverse direction to an initial position, a back spacing mechanism for moving said carriage in said reverse direction a predetermined distance on each operation there of and means controlled by said carriage in a predetermined part of its path of travel for disabling said back spacing mechanism to back space said carriage.

3. In a telegraph recorder, a carriage movable step-.by-step in an advancing letter spacing direction and continuously in a reverse direction from any point in its path of travel to an initial position in response to a carriage return signal, a signal controlled back spacing mechanism and means operated by said mechanism for back spacing said carriage a predetermined distance on each operation thereof only when said carriage is in a predetermined part of its path of travel.

4. In a telegraph machine, a carriage, a rack on said carriage, a pinion engageable with said rack and rotatable step-by-step to advance said carriage in a letter spacing direction, said rack being disengaged from said pinion to effect the normal carriage return movement of said carriage, an element rotatable in only one direction coupled to said pinion for rotating the same to advance said carriage, means for uncoupling said element from said pinion to permit rotation of said pinion in a reverse direction a predetermined amount and corresponding return movement of said carriage, and means for recoupling said element to said pinion after the reverse rotation thereof whereby rotation thereof in said one direction effects advancement of said carriage.

5. In a telegraph machine, a carriage, a rack on said carriage, a first pinion engageable with said rack and rotatable step-by-step to advance said carriage in a letter spacing direction, said rack being disengaged from said pinion to effect the return movement of said carriage, a second pinion, means for lnterposing said second pinion between said rack and first pinion whereby rota tion of said first pinion in a direction to normally advance said carriage efiects corresponding movement of said carriage in a reverse direction.

6. In a telegraph machine, a carriage, a rack on said carriage, a first pinion engageable with said rack and rotatable stepby-step to advance said carriage in a letter spacing-direction, said rack being disengaged from said pinion to effect the return movement of said carriage, a second pinion engaged with said first pinion and nor mally disengaged from said rack, means responsive to a first code group of signals to engage said second pinion with said rack and disengage said rack and said first pinion whereupon rotation of said first pinion in a direction to normally advance said carriage effects corresponding movement thereof in a reverse direction and means responsive to a second code group to re-engage said rack with said first pinion and disengage said second pinion therefrom.

7. In a telegraph machine, a carriage, a carriage advancing mechanism normally operative to advance said carriage in a letter spacing direction a predetermined distance on each operation thereof, a signal controlled device and means operated by said device to condition said carriage advancing means to efiect movementof said carriage in a reverse direction in conjunction with the receipt of code groups normally effecting advancement thereof.

8. In a telegraph machine, a carriage, a carriage advancing mechanism normally operative to advance said carriage in a letter spacing direction a predetermined distance on each operation thereof, a control for said mechanism, means responsive to one predetermined code group to operate said control to condition said carriage advancing means to cause movement of said carriage in a direction opposite to said letter spacing direction in response to code groups normally causing advancement thereof and means responsive to a second predetermined code group to operate said control to restore said carriage ad-v vancing means to a normal condition.

9. In a telegraph machine, a carriage, a carriage advancing mechanism normally operative to advance said carriage in a letter spacing-direction a predetermined distance on each operation thereof, a control for said'mechanism, means responsive to one predetermined code group to operate said control to condition said carriage advancing means to cause movement of said carriage in a direction opposite to said letter spacing direction distances corresponding to the advancement thereof in a letter spacing direction in response to code groups normally causing such advancement and means responsive to a second predetermined code group to operate said control to restore said carriage advancing means to a normal condition.

10. In a telegraph machine, a carriage, a rack on said carriage, a pinion engageable with said rack and rotatable step-by-step to advance said carriage in a letter spacing direction, said rack being disengaged from said pinion to effect the normal carriage return movement of said car-' riage, an element rotatable in only one direction, coupling means including said pinion between said element and said rack for advancing said carriage on rotation of said element, signal controlled means and means including said signal controlled means for controlling said coupling means to efiect return movement of said carriage predetermined distances.

HERBERT ANGEL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

